Ferrous alloy



Patented Mar. 8, 1949 FERROUS ALLOY Arthur '1. Cape, Columbus, Ohio,assignor to Coast Metals, Inc., Canton, Ohio, a corporation of DelawareNo Drawing. Application May 29, 1947, Serial No. 751,473

6 Claims.

This invention relates generally to ferrous alloys, but has referencemore particularly to an alloy which is especially adapted for use in theform of weld rods for hard facing purposes.

In my U. S. Patent No. 2,313,420, I have described an alloy which isused for hard facing various articles which have been subjected to wearand abrasion, but which is especially adapted for hard facing hotshears, hot working dies, soaking pit tongs, and devices for carrying ortransporting hot ingots and the like. The alloy derives its usefulnessfrom the fact that it not only has high resistance to wear and abrasion,but has high resistance, as well, to heavy and repeated impacts, that isto say, it possesses high mechanical strength. It is also resistant tochemical corrosion and to oxidation at high temperatures, has thequality of being capable of forming a sound bond with the base metal,has a high viscosity, in the molten condition, such as to permitexceedingly easy application thereof to the base metal, and is furthercharacterized by the fact that it is hard and tough, its hardness beingrelatively low from the point of view of indentation hardness, except inthe upper portion of its carbon range, where its hardness may be 60+Rockwell C. The wear resistance is high at all hardnesses, which rangefrom 40 to 60+ Rocklell C.

I have discovered that by a judicious selection of a portion of theranges of the elements of the alloy disclosed in the aforesaid patent,and by adding to the alloy silicon in appreciable amounts, 1. e., fromabout 1.5% to about 4%, I am enabled to materially increase the hardnessof the alloy, without having to increase the carbon content thereof.Moreover, I find that by the addition of silicon to the alloy in amountswithin the range referred to, I am enabled to maintain the hardness ofthe alloy for any given cobalt content of the alloy.

As the cobalt content of an alloy of this character is increased, thereis a tendency for the alloy to lose its austenitic state or condition,and this is likewise true when the silicon content of the alloy isincreased. Moreover, as the cobalt content of the alloy is increased,the hardness of the alloy is increased, without increasing thebrittleness of the alloy. Silicon likewise increases 2 the hardness ofthe alloy, but does increase the brittleness thereof.

Since the cobalt increases the hardness of the alloy much less rapidlythan does silicon, I find that by properly balancing the proportions ofcobalt and silicon, I produce highly desirable and improved propertiesin the alloy, with a general increase in the hardness range thereof to50 to Rockwell C.

The weld rod, according to my improvement, is preferably made from aferrous alloy containing from about 2.75% to about 4.25% carbon,chromium in an amount of from about 6% to about 18%, nickel in an amountof from about 3% to about 10%, molybdenum in an amount of from about 3%to about 9%, cobalt in an amount of from about 14% to about 27% andsilicon in an amount of from about 1.5% to about 4%, the balance of thealloy being substantially all iron.

A preferred alloy within the foregoing range will contain about 3.5%carbon, about 16% chromium, about 5% nickel, about 7% molybdenum, about20% cobalt, about 2% silicon, and about 53.5% iron.

I claim:

1. A ferrous alloy particularly adapted for hard facing purposes, saidalloy containing carbon in the amounts from about 2.75% to about 4.25%,about 6% to about 18% chromium, about 3% to about 10% nickel, about 3%to about 9% molybdenum, about 14% to about 27% cobalt, and about 1.5% toabout 4% silicon, the remainder of said alloy being substantially alliron.

2. A Weld rod for hard facing purposes, said rod comprising a ferrousalloy containing carbon in the amounts from about 2.75% to about 4.25%,about 6% to about 18% chromium, about 3% to about 10% nickel, about 3%to about 9% molybdenum, about 14% to about 27 cobalt, and about 1.5% toabout 4% silicon, the remainder of said alloy being substantially alliron.

3. A heat and abrasion resistant facing comprising a ferrous alloycontaining carbon in the amounts from about 2.75% to about 4.25%, about6% to about 18% chromium, about 3% to about 10% nickel, about 3% toabout 9% molybdenum, about 14% to about 27% cobalt, and about 1.5% toabout 4% silicon, the remainder of said alloy being substantially alliron.

4. A ferrous alloy particularly adapted for hard facing purposes, saidalloy containing about 3.5% carbon, about 16% chromium, about 5% nickel,about 7% molybdenum, about 20% cobalt and about 2% silicon, theremainder of the alloy being substantially all iron.

5. A Weld rod for hard facing purposes, said rod comprising a ferrousalloy containing about 3.5% carbon, about 16% chromium, about 5% nickel,about 7% molybdenum, about 20% cobalt and. about 2% silicon, theremainder of the alloy being substantially all iron.

6. A heat and abrasion resistant facing comprising a ferrous alloycontaining about 3.5% carbon, about 16% chromium, about 5% nickel, about7% molybdenum, about 20% cobalt and about 2% silicon, the remainder ofthe alloy being substantially all iron.

ARTHUR T. CAPE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,208,116 Cape et al. July 16,1940 2,313,420 Cape Mar. 9, 1943 OTHER REFERENCES

